Appearing on the September 29 cover of Billboard magazine, the 31-year-old singer opens up about the struggle to stay thin in the music industry. "During the promotion of my album Stripped [in 2002], I got tired of being a skinny, white girl," Aguilera says. "I am Ecuadorian but people felt so safe passing me off as a skinny, blue-eyed white girl."

"The next time my label saw me, I was heavier, darker and full of piercings!" the five-time Grammy Award winner laughs. "Let me tell you, that wasn't an easy pill for them to swallow. I had gained about 15 pounds during promotion and during my Stripped tour [with Justin Timberlake, 31]. They called this serious emergency meeting about how there was a lot of backlash about my weight. Basically, they told me I would affect a lot of people if I gained weight -- the production, musical directors."

"[They claimed] people I toured with would also miss out if I gained weight because I would sell no records or tickets for my shows," she adds. "I was young, so I lost the weight quickly and was toothpick thin during Back to Basics promos and touring."

The "Your Body" singer, dating production assistant Matthew Rutler, had finally had enough in 2012. "I told them during this Lotus recording, 'You are working with a fat girl. Know it now and get over it.' They need a reminder sometimes that I don't belong to them. It's my body," Aguilera tells the magazine. "My body can't put anyone in jeopardy of not making money anymore—my body is just not on the table that way anymore."

After the critical and commercial failure of her 2010 album Bionic, Aguilera hopes Lotus (in stores November 13) will remind music lovers of her true talent. "This album represents a celebration of the new me, and to me the lotus has always represented this unbreakable flower that withstands any harsh weather conditions in its surroundings, that withstands time and remains beautiful and strong throughout the years."

"Once I could start writing my own songs, beginning with Stripped, I tried to infuse as much as I could to promote strength and inspire people with that message," Aguilera explains. "And now I'm at a place at 31, where the last time I felt this way was when I was 21 with Stripped and I had a lot to say and a lot to express."